Harmful emissions remain a concern for many engine systems, particularly as engines are being subjected to increasingly strict emission standards. The emission standards for engines may vary depending on the type of engine. For example, diesel engines may have different standards than dual-fuel engines. Engines may use aftertreatment systems to treat exhaust exiting the cylinders of an engine. However, aftertreatment systems for engines operating in dual-fuel modes currently encounter a number of challenges. Such challenges include reducing short-chain hydrocarbons such as methane and ethane during the dual-fuel mode, maintaining stable performance of catalysts, tolerating catalysts under poisoning conditions, and diagnosing the health of catalysts onboard.